Embodiments of the invention relate generally to motor control systems and, more particularly, to a board-level motor control system having integrated protection and control components.
One type of system commonly used in industry that performs power conversion is an adjustable speed drive, also known as a variable frequency drive (VFD). A VFD is an industrial control device that provides for variable frequency, variable voltage operation of a driven system, such as an AC induction motor. In use, a VFD is often provided as part of a motor control system and overall control and protection assembly that includes the VFD as well as an arrangement of input/output fuses, disconnects, circuit breakers or other protection devices, controllers, filters, sensors, and a bypass assembly that includes one or more of a bypass contactor and soft starter that provide alternate control paths or mechanisms for controlling the driven system.
As a general rule in known motor control systems, the VFD and associated protection and control devices, generally indicated as components 2 in FIG. 1, are provided as discrete components having their own housings 4. The discrete, housed components 2 are positioned within a large metal enclosure 6. The arrangement of components 2 is fixed to a support within the enclosure 6, such as a DIN rail for example, with wiring 8 being provided between the components 2 to provide for electrical connectivity and/or communication therebetween. When the overall collection of components 2 is assembled as a unit, the enclosure 6 required to house the components 2 becomes quite large and bulky. Also, the large amount of wiring 8 required between the components 2 can hinder accessibility to the components 2, increases installation time and the potential for failure due to wiring and wiring connections, and reduces the overall efficiency of the motor control system.
It would therefore be desirable to provide a motor control system with a minimized footprint, increased efficiency, improved operational flexibility, and the ability for shared thermal management for multiple components.